ARAMIS (American Rheumatism Association Medical Information System) is a multi-institutional rheumatic disease computer databank system containing detailed clinical information about 6,000 patients, 30,000 patient visits, and 20,000 patient years of observation, operating from the IBM 370/168 computer at Stanford University and available nationally through a communication network. In the present phase evolution toward the National Data Resource for Arthritis recommended in the Arthritis Plan and in the National Arthritis Act will be continued. The evolving system will be used in a multi-institutional investigative program directed at major clinical problems in the rheumatic diseases. The ARAMIS data banks will serve to evaluate tests, procedures, and observations to determine their relative value in particular decision situations and to provide guidance to the clinician in choice of investigative procedures. Over fifty associated investigators will undertake over fifty specific clinical studies under this program project. A population-based study will explore factors relevant to outcome at ten to fifteen years in rheumatoid arthritis. Long-term functional results of joint replacement will be studied. Criteria for quality of care, based upon outcome, will be elaborated. Disease criteria for scleroderma, systemic lupus, and polymyositis will be evolved and tested. The influence of psychosocial variables upon patient outcome will be explored. A variety of additional studies will investigate questions of classification, prognosis, and management in the rheumatic diseases. The computer system will be developed for transfer to other computer systems and an office-based information system evaluated. With this project, ten years of development at several institutions is brought to bear upon major clinical questions, and the groundwork is established for the National Arthritis Data Resource.